Surgical systems and methods for dynamic virtual boundary adjustment

Abstract

A surgical navigation system and method of operating the same involve a pointer tool and a localizer configured to track the pointer tool. Controller(s) is/are coupled to the localizer and are configured to generate a virtual boundary relative to a bone at a surgical site. The virtual boundary has a shape that delineates a region of the bone to be removed from a region to be avoided. The controller(s) identify, with the localizer, a position of one or more landmarks at the surgical site in response to the pointer tool touching the one or more landmarks at the surgical site. The controller(s) revise the shape of the virtual boundary based on the position of the one or more landmarks.

What is claimed is: 
     
         1 . A surgical system, comprising:
 a pointer tool;   a navigation system comprising a localizer configured to track the pointer tool;   a surgical manipulator configured to support and move a surgical instrument, wherein the surgical instrument includes an energy applicator configured to manipulate a bone at a surgical site; and   one or more controllers coupled to the navigation system and the surgical manipulator and being configured to:
 generate a virtual boundary relative to the bone, wherein the virtual boundary comprises a shape that delineates a region of the bone to be removed by the energy applicator from a region to be avoided by the energy applicator; 
 identify, with the navigation system, a position of one or more landmarks at the surgical site in response to the pointer tool touching the one or more landmarks at the surgical site; 
 revise the shape of the virtual boundary based on the position of the one or more landmarks; and 
 control the surgical manipulator to constrain the energy applicator from movement beyond the virtual boundary. 
   
     
     
         2 . The surgical system of  claim 1 , wherein the one or more controllers revise the shape of the virtual boundary based on the one or more landmarks defined by being configured to generate one or more notches in the shape of the virtual boundary. 
     
     
         3 . The surgical system of  claim 1 , wherein the one or more landmarks at the surgical site are defined relative to a retractor that retracts soft tissue adjacent to the bone to expose the bone. 
     
     
         4 . The surgical system of  claim 3 , wherein the one or more controllers revise the shape of the virtual boundary such that the shape of the virtual boundary avoids the retractor. 
     
     
         5 . The surgical system of  claim 1 , wherein the one or more controllers are configured to control the surgical manipulator to move the energy applicator to remove the region of the bone delineated by the virtual boundary to prepare the bone for receiving an implant. 
     
     
         6 . The surgical system of  claim 5 , wherein to remove the region of the bone delineated by the virtual boundary, the one or more controllers control the surgical manipulator in a semi-autonomous mode whereby the surgical manipulator is configured to semi-autonomously advances the energy applicator along a tool path defined relative to the bone. 
     
     
         7 . The surgical system of  claim 5 , wherein:
 the surgical manipulator comprises a sensor configured to measure external forces/torques applied to the surgical instrument; and   to remove the region of the bone delineated by the virtual boundary, the one or more controllers are configured to control the surgical manipulator in a manual mode whereby the surgical manipulator advances the energy applicator in response to the external forces/torques applied to the surgical instrument.   
     
     
         8 . The surgical system of  claim 1 , wherein:
 a bone tracker is coupled to the bone; and   the localizer configured to detect the bone tracker to track the bone.   
     
     
         9 . The surgical system of  claim 1 , wherein the navigation system comprises a boundary generator module configured to generate the virtual boundary and revise the shape of the virtual boundary, and wherein the boundary generator module is further configured to:
 generate the shape of the virtual boundary based on implant data including a definition of a shape of an implant for the bone.   
     
     
         10 . A surgical system, comprising:
 a pointer tool;   a navigation system comprising a localizer configured to track the pointer tool;   a surgical manipulator configured to support and move a surgical instrument, wherein the surgical instrument includes an energy applicator configured to manipulate a bone at a surgical site; and   one or more controllers coupled to the navigation system and the surgical manipulator and being configured to:
 generate a virtual boundary relative to the bone, wherein the virtual boundary comprises a shape that delineates a region of the bone to be removed by the energy applicator from a region to be avoided by the energy applicator; 
 identify, with the navigation system, a position of one or more landmarks at the surgical site in response to the pointer tool touching the one or more landmarks at the surgical site; 
 revise the shape of the virtual boundary based on the position of the one or more landmarks; and 
 control the surgical manipulator to move the energy applicator to remove the region of the bone delineated by the virtual boundary to prepare the bone for receiving an implant. 
   
     
     
         11 . The surgical system of  claim 10 , wherein the one or more controllers revise the shape of the virtual boundary based on the one or more landmarks defined by being configured to generate one or more notches in the shape of the virtual boundary. 
     
     
         12 . The surgical system of  claim 10 , wherein the one or more landmarks at the surgical site are defined relative to a retractor that retracts soft tissue adjacent to the bone to expose the bone. 
     
     
         13 . The surgical system of  claim 12 , wherein the one or more controllers revise the shape of the virtual boundary such that the shape of the virtual boundary avoids the retractor. 
     
     
         14 . The surgical system of  claim 10 , wherein to remove the region of the bone delineated by the virtual boundary, the one or more controllers control the surgical manipulator in a semi-autonomous mode whereby the surgical manipulator is configured to semi-autonomously advances the energy applicator along a tool path defined relative to the bone. 
     
     
         15 . The surgical system of  claim 10 , wherein:
 the surgical manipulator comprises a sensor configured to measure external forces/torques applied to the surgical instrument; and   to remove the region of the bone delineated by the virtual boundary, the one or more controllers are configured to control the surgical manipulator in a manual mode whereby the surgical manipulator advances the energy applicator in response to the external forces/torques applied to the surgical instrument.   
     
     
         16 . The surgical system of  claim 10 , wherein:
 a bone tracker is coupled to the bone; and   the localizer configured to detect the bone tracker to track the bone.   
     
     
         17 . The surgical system of  claim 10 , wherein the navigation system comprises a boundary generator module configured to generate the virtual boundary and revise the shape of the virtual boundary, and wherein the boundary generator module is further configured to:
 generate the shape of the virtual boundary based on implant data including a definition of a shape of the implant for the bone.